Results: Postoperative acute kidney injury occurred in 44% of the cohort. At 5-year follow-up, 17% of children had hypertension, a 10-fold greater rate than the general pediatric population. Overall, 8% has microalbuminuria, 13% had estimated glomerular filtration rate < 90 mL/min/1.73 m2 and 1% had eFGR < 60 mL/min/1.73 m2. Chronic kidney disease was documented in 18%. Only 4% of children were seen by a nephrologist during follow-up. Renal outcomes did not differ between children who had postoperative acute kidney injury and those who did not.